When a character uses the hamstringcombat maneuver, they attempt to knock an opponent over by cutting the tendons behind the knee. A successful use of the skill results in a prone opponent with a level 2 wound to the leg. Additionally, if the weapon used has flares, there is a chance that the weapon will flare when the hamstring is successful, thus making feras weapons particularly deadly when combined with hamstring, as this skill bypasses the attack roll system and instead relies on the combat maneuver system. Hamstring takes critical weighting or damage weighting on the weapon used into account.

While, in life, a severed hamstring will cripple the victim, a creature affected by the Hamstring maneuver can still stand up. Though, if Hamstring is used a second time on the same victim, it will sever the leg, preventing the victim from standing again.

Since the primary function of hamstring is to bypass the target's armor in order to do highly specific damage to the hamstring muscles, padding, resistances, flares, armor divisors, and the like are all bypassed when the maneuver succeeds.

Having two weapons provides a sizeable bonus to this maneuver, while targeting an enemy with more than two legs provides a penalty.